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Toilet bowl effect on first flight. What's up?

Discussion in 'Pro/Adv Discussion' started by koviatt, Jul 24, 2015.

  1. koviatt

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    Yes, I calibrated three times just get it right and the last time got a green go ahead. So I put the unit in P mode and did an auto take off. P3P lifted of nicely, then started to swirl around and around larger and larger circles to nearly 20 foot diameter swirls. I got it under control and set it down. Whew. thank goodness I have been flying for a while and knew what to do. Anyway, I am new to this P3P forum, had a P1 and a missing P2. So what's going on? Is there a firmware update?
    Kent
     
  2. Andy Collins

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    what was the compass mod value?
     
  3. msinger

    Approved Vendor

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    Try calibrating the IMU on a perfectly level surface.
     
  4. ianwood

    ianwood Taco Wrangler
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    TBE not caused by IMU. IMU error would be consistent movement in one direction.

    OP, you need to make sure compass calibration is good and the compass isn't magnetized. Check the mod value away from all metal and magnetic sources. Do the calibration in the middle of a grass field, absolutely no metal or man made objects within 15ft. Check mod again.
     
  5. koviatt

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    1478
     
  6. Foosy

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    Did you get any warnings?
    Usually if there is a compass issue, you will get a red message on top of the app.

    I was boating, and decided to launch my p3p off the boat. Didn't have a lot of surface other than a table. Calibrated compass, launched, and 6 ft up in the air I get a compass error. Brought it back immediately, calibrated again, launched, same thing. Brought it back and thought my phantom went bad. Looked at the table, it was a plastic surface- but was held on a metal pole. The calibration just above that completely threw my compass off. Moved it away and re calibrated again, this time it flew with no problems.

    Conclusions:
    1. Metal objects are not always visible. Make sure to calibrate away from them.
    2. Never, never, never fly with a compass error warning.
     
    bobmyers likes this.
  7. Meta4

    Meta4 Moderator
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    3. Another example of how calibrating every time can be a bad idea and rather than improving flight safety, it may cause serious problems.

    You want your compass to be accurate in the magnetic environment up where you are flying - not in the contaminated magnetic environment you may be calibrating in.
     
  8. Sprague

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    Something I'm sure everyone knows but I recently found even my watch to disrupt the compass calibration process. Remarkable...
     
  9. vgt

    vgt

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    This. no reason to calibrate before every flight. Get a GOOD calibration, then leave it alone unless you modify something or travel a significant distance.